VAPB
VAPB (vesicle-associated membrane protein-associated protein B/C, also known as VAP-B, VAP-C and ALS8) is an endoplasmic reticulum-anchored protein of the VAP family. It mediates contact sites between the ER and endosomes and contributes to the unfolded protein response and calcium homeostasis. Browse Assay Genie's current range of VAPB research reagents below, or read on for the biology behind the target.
VAPB is an endoplasmic reticulum (ER)-anchored protein that mediates the formation of contact sites between the ER and endosomes. It does this by interacting with proteins that carry an FFAT motif, such as STARD3 or WDR44. Its interaction with STARD3 depends on phosphorylation of the FFAT motif. Through WDR44, VAPB participates in the export of neosynthesised proteins.
VAPB also takes part in the ER unfolded protein response (UPR), where it induces the activity of ERN1/IRE1. It is involved in the regulation of cellular calcium homeostasis. These roles place the VAPB protein at the interface between ER organisation, protein export and stress signalling.
According to NCBI Gene, the VAPB gene encodes a type IV membrane protein found in plasma and intracellular vesicle membranes. It occurs as a homodimer and as a heterodimer with VAPA, and it can interact with VAMP1 and VAMP2, so it may be involved in vesicle trafficking. VAPB belongs to the VAMP-associated protein (VAP) family and to the HGNC motile sperm domain containing gene group. Its aliases include VAP-B, VAP-C and ALS8, and its previous name was VAMP (vesicle-associated membrane protein)-associated protein B and C. Mouse and rat each have a Vapb ortholog.
VAPB tethers the ER to endosomes through FFAT motif-containing partners such as STARD3 and WDR44, making it a central protein for studying membrane contact sites.
VAPB participates in the ER unfolded protein response by inducing ERN1/IRE1 activity, which makes it relevant to ER stress signalling research.
VAPB is involved in the regulation of cellular calcium homeostasis, linking ER membrane organisation to calcium handling.
VAPB interacts with VAMP1 and VAMP2 and, via WDR44, participates in neosynthesised protein export, supporting studies of vesicle trafficking.
VAPB is an ER-anchored protein that mediates contact sites between the ER and endosomes by binding FFAT motif-containing proteins such as STARD3 and WDR44. It also induces ERN1/IRE1 activity in the unfolded protein response and is involved in regulating cellular calcium homeostasis.
VAPB is also called VAP-B, VAP-C and ALS8. Its full name is VAMP associated protein B and C, and the UniProt entry is named vesicle-associated membrane protein-associated protein B/C. The previous HGNC name was VAMP (vesicle-associated membrane protein)-associated protein B and C.
VAPB belongs to the VAMP-associated protein (VAP) family and forms a heterodimer with VAPA. Mouse and rat both have an ortholog named Vapb. Check the datasheet of any product for its validated reactivity.
Other VAP family members, FFAT motif partners and unfolded protein response and vesicle trafficking proteins with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O95292; product specifications from Assay Genie datasheets.